Allows up to 16 MB of expansion RAM. The expansion memory can be provided by a combination of 30-pin SIMM RAM on an internal card, a Commodore 17xx-series REU (or a clone) plugged into the RAM Port, or a GeoRAM.

Provides its own copy of JiffyDOS, allowing accelerated operation with any other JiffyDOS-equipped disk device, as well as shorthand commands (DOS Wedge) to conveniently access any other connected storage devices.